Homomorphic cameo filter for pattern recognition that is invariant with changes in illumination
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Updated: Jul 9, 2026

Motion-Acuity Test for Visual Field Acuity Measurement with Motion-Defined Shapes
Published on: February 23, 2024
1Centre d'Optique, Photonique et Laser, Départment de Physique, Université Laval, Quebec G1K 7P4, Canada.
Abstract:
We introduce a new matched filter method that yields correlation peaks that are invariant with changes in the illumination of any targets. A scene containing objects at unknown locations is first subjected to a logarithmic transformation that changes the multiplicative constant to an additive background, which is then discriminated against by means of a composite filter containing a cameo of the true target and a term with which to discriminate against other false targets. Experimental results are shown.
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